I’ve been interested in astonomy my whole life, and a few years back, I got a second-hand Meade LX-10 telescope. This is a 8″ diameter scope… definitely not a toy. It is great for planetary viewing and can even track the planets as the Earth turns. I have used it from time to time to try to take some pictures of celestial objects, but not very good ones. Astrophotography is a growing interest of mine now and I found the learning curve quite steep. I’m throwing together everything I’ve learned over the past couple of years including links to software and such into a few posts. There are multiple steps involved in this project and it took me a long time, working here and there and amongst about 1000 other projects, to finally get everything together for this.

To take amazing amateur astrophotography images you need to decide whether you want to look at deep space objects (DSO) like galaxies or nebulae, or if you want to focus on planetary viewing (within our own solar system). You don’t really want to zoom very much if you want DSO images because zooming narrows your field of view and most DSOs you want to get are very dim so you don’t want to zoom in to make their light spread out across your eye or camera sensor too much, you want bright pictures. You can take some amazingly cool pictures with just a DSLR and a “barn door” tracker. (This is just a device that rotates counter to the Earth’s rotation so your camera will continue pointing at the same object for minutes or hours at a time, meaning it moves a full 360 degrees in 24 hours).

In my case, I want to do a little of both planetary and DSO. So I have my LX-10 telescope, which has an 8″ diameter mirror, meaning it can collect a lot of light, and it has a tracker so I can point a camera at one point in the sky as long as I want. However, unless you perfectly align the scope with true celestial north, the scope will still drift a bit over the night. This is because it is an open control system. You just point it at a star, turn it on and hope you aligned it well when you started. The best images are taken with closed-loop control systems. That is, they continuously look to see if it is drifting off target, then takes actions to move back on target when needed. This guy has my telescope and has taken some amazing pictures of planets, sunspots, and DSOs. Some are mindlbowingly good! To be fair, he’s using some reducer lenses like this one to change his F-stop to make it much quicker (for example F/3.75 and F/4.6 in some images), oh and he’s using a 4x Powermate lens a lot which costs as much as I spent on my entire telescope… But what is great about his site is that he tells all the settings he used for the images. This is similar to Reddit’s astrophotography subreddit.

My scope is what they call “slow,” “long,” or “dark.” This refers to the F-stop number. This is also called the focal ratio or relative aperture. It is a ratio of the len’s focal length and the diameter of the scope. THe focal length of my telescope is 2000mm. And the aperture is 8″ or 203mm. The F-stop of this would be about 2000mm / 200mm = 10. So this means my scope is a F/10 lens. The higher the f-stop number is, the darker the image will be (all other things being equal) when compared to a lens with a smaller f-stop number. For example an F/4 is considered a pretty “fast” telescope. My F/10 number basically means that to take a nice bright picture of Jupiter for instance, I need to play with the “sensitivity” or ISO number of the camera sensor (used to be film) as well as the duration I leave the shutter open on the camera.

You might say, “Well I can just crank up the sensitivity then. Higher sensitivity will make the image come out brighter, right?” The answer is yes and no. You can raise the sensitivity, but then a lot of other things (such as heat) can trigger a pixel to register a value in a digital camera. This will increase the noise in the image, making it staticy.

You might then think “Ok, the other option is to just open the shutter for a long time, exposing the camera sensor to more light over a longer time period.” yeah… not really. This can work as well, however you will increase the overall light pollution in your images and worse, you risk blurring the image. Since the Earth keeps on spinning, objects in a fixed telescope’s field of view move. Without tracking perfectly, long exposures will be blurred.

Even if you can fix all that, there’s blurring you simply cannot fix. This is due to heat inversion in the air column between you and the object you are viewing. The Hubble space telescope was designed to fix this problem… by simply being above all the air on earth orbiting in a pretty high orbital plane (at the farthest reach that the space shuttles could fly). Air at different temperatures has different densities. This acts like a prism to bend the shape of a beam of light. Look at a straw or pencil in a glass of water. Notice how it looks like it’s broken in half at the interface of the water and the air? That’s an example of the different densities acting like a prism. Since air is, well, air… it is gaseous and mixes and moves around a lot. It is in constant motion (unlike the water in your glass compared to the air sitting on top of it.) Hot air rises and cool air falls, making all sorts of weird prism effects in our viewfinder. In the column of air between you and the top of the atmosphere where Hubble is, there’s also a lot of dust. The dust as well as the temperature inversions is what makes starts look like they are twinkling.

Side note: Planets don’t twinkle in the sky when viewed by eye. This is because a star is so far away, you are only seeing it as a point light. This makes it easy for dust or temperature inversion to affect your view of it. But planets are much closer, and their light is spread slightly wider across the retina in your eye. This means there much less of a chance that a mote of dust will block it, or temperature inversion will guide the light too far from your retina.

So how do you fix the problem of having a dark image from the telescope without getting errors from too high of a sensitivity setting or blurring from too long an exposure and temperature inversions? You can thank Woz for the home computer! Using a laptop, I’m going to connect a closed-loop control system to my computer to track the objects I want to image very closely, reducing blur of long exposure images. I’m also going to take multiple images of the same object, then do a process called “stacking” where a computer algorithm will take the sharpest views of different parts of the planet, for instance, and stitch them together into a composite image that is overall much sharper. Then I’ll be able to do some image processing on the composite image to get some great results. Stay tuned for more posts on this theme!

I’ve finally gotten jealous enough for the astrophotography subreddit to get back to work on this project. Jess bought me a Meade LX10 8″ diameter telescope several years ago for my birthday. I’ve used it quite a bit to view planets and try to take deep sky astrophotography pictures. This telescope isn’t one of those fancy ones you can type in whatever cool thing you want to see and it’ll drive itself to point right to it, that’s called a “GO TO”. Rather it has a simple “barn door” tracker motor. Basically, if you align to perfect true north, and set the wedge (the thing that mounts the telescope to the tripod) to your latitude, whatever you point the scope it will stay in view for hours in the eyepiece. If I know where to look, I can attach a camera to the scope and leave the shutter open and get some amazing pictures of nebulae and galaxies.

Being that I’m no good at polar alignment, I decided a few years ago to build an arduino interface that will connect my scope to my computer. The way this works is that I attach a webcam to the spotter scope (the small telescope that helps you find stuff) which looks at a particular star. The webcam pipe data into a program that sends signals out to the arduino to move the scope to keep the star in the same part of the webcam’s view. This way, I don’t have to be perfectly polar aligned, the software will help adjust the position of the scope for me.

I went on the hunt for a webcam that would work well with Windows and linux. This is because a lot of people are buying Raspberry Pi boards,connecting a webcam to them and attaching the whole setup to the telescope. Right now I’m testing on a windows machine so I need a webcam that’ll play well with both. I looked up the Linux Universal video Class (UVC) drive list to find a good modern camera. This list shows a good number of webcam models and brands that are known to work natively in recent linux distros.

The camera I landed on is the Logitec HD Webcam C270. It is a very cheap 720p 3 megapixel webcam. That’s overkill for the telescope, but it’s a good general use webcam and we can use it for video chats and such as well. This means my solution to attaching the camera to the scope can’t be permanent.

I keep a bunch of 3/4″ PVC pipes and connectors in the garage for prototyping, so I grabbed a 3/4-inch T connector. This connector can easily accommodate my 1″ outer diameter sighting scope.

The scope doesn’t fit perfectly, so I added some 2mm sticky-backed craft foam for a snug pressfit. (On a side note, I can’t tell you how useful it is having this kind of foam in the toolbox for all sorts of random purposes. I use it all the time) To accommodate the webcam, I used a hacksaw to cut a portion of the PCV connector off as shown. Then I wrapped a 3/8″ piece of foam on each of the cut edges of the PVC where it will touch the camera. This will help the camera seat well and stay in place when I attach it to the scope.

Finally, I used a smooth “ouchless” hair tie to hold the camera to the PVC tightly and aligned the camera with the hole in the PVC T-joint. Again, believe it or not, these hair ties are pretty useful for random jobs. In fact, I use a 8-inch smooth headband made of the same material to hold on my cheapo dew shield (more on this in another post.)

The final product is easy to use and quite robust. I think it’ll work quite well with my the rest of my setup. Since I’m still working that all out, I’ll post more as I learn more.

Yesterday was a great Saturday for exploring new places. Adam and I watched our first roller derby game. We sat in “suicide seating” which was on the ground right on the rink. Even better, our home team – the Charlotte Roller Girls – won their bout. Next Adam took me to a great burger joint called the Kickstand. It was great food and I surprisingly (or maybe not too surprisingly) loved having avocado on my burger.

In honor of exploring new places, I felt inspired to tackle the skill of changing signs in photos to say what you want. Here is the original photo I took at a North Carolina beach.

Here is version 1.

Version 2.

Version 3.

Version 4.

Version 5.

This time around I don’t have a very strong favorite and I like them all. Take all of them as a “sign”

After yesterday’s photo word art centered around the quote “You can’t plow a field by turning it over in your mind“, I still had remnants of inspiration. Last summer my father came to visit, and I was thinking about our adventures because he is going to be returning again. Last visit, he discovered an amazing privately owned lake that is open to public visitors. I took the following photo at that lake.

I wanted simplicity with my creations. Here are my afters.

And…

Last, my favorite.

I am in love with the above. I really see my self taught Photoshop skills growing in the above transformation. Yay for progress!

I was listless last night when I stumbled across this quote: You can’t plow a field by turning it over in your mind. It inspired me to use a tree picture I had taken and turn it into inspirational word art.

Here is the before.

Here are the afters.

This is my second favorite of the group.

A friend commented that the text was hard to read, so at the last moment I created the version that became my favorite of the bunch.

In honor of my word of the year “Be”, I played around in photoshop using a dandelion picture I took on my summer road trip to Wisconsin and the quote, “If you want to be happy, then be”. These are my results:

This past summer Adam and I went on a road trip to my family farm. My great uncle currently leaves there and owns some peacocks. This is the original picture I took of one of his peacocks. It inspired the idea of showing your true colors and being your true self.

From that idea, I found this Dr. Seuss quote: “Be who you are and say what you feel, because those who mind don’t matter and those who matter don’t mind.” Isn’t it lovely?

I played with font types, font sizes, and font spacing. These are the resulting beauties.

The one above uses the free font Hero, and the one below uses the free font Metropolis.

I thought the font was too small so I made it bigger.

I also like the idea of the font being hard to read – like a mirage of thought.

I researched to find out which Seuss book this quote came from and it seems to be a mystery. Many sources site the quote (“Be who you are and say what you feel, because those who mind don’t matter and those who matter don’t mind.”) to Seuss, but there is a similar quote by Bernard Baruch which states “Those who mind don’t matter, and those who matter don’t mind.” Anyone have insight over this mystery?